• The Journal of the Acoustical Society of Korea
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• v.19 no.3
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• pp.77-85
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• 2000

Laboratory determinations of acoustic and physical properties in Korea Strait sediment were carried out. Sediment sound velocimeter(SSV) was employed to measure the sound velocity of sandy sediment. Distribution patterns of the acoustic and physical properties are controlled by sediment texture. The study area is divided into three provinces(mid-shelf, shelf margin and enough) based on the acoustic and physical properties. This classification matches well with the previous result[14] based on the systems tracks and depositional systems. We suggest a geoacoustic model of the Korea Strait that replacing the old model of Briggs and Fisher[5].

• Proceedings of the Korea Information Processing Society Conference
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• 2016.10a
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• pp.497-500
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• 2016

최근 임베디드 소프트웨어의 신뢰성과 안전성을 보장하기 위하여 코딩룰인 MISRA-C를 자동차 뿐만 아니라 군사, 의료 분야등 광범위한 분야에서 이용하고 있다. 하지만 MISRA-C가 자동차 시스템분야의 MISRA 가이드를 이용하여 개발되었기 때문에 타 분야의 분야별 특성을 모두 고려하지 못한다는 문제점이 제시되고 있다. 따라서 본 논문에서는 향후 의료기기 분야의 특성을 고려한 코딩룰을 제시하기에 앞서, 의료기기 소프트웨어에서의 코딩룰 필요성을 제시한다. 이를 위해 개발 단계의 의료기기 소스코드에 MISRA-C를 적용하여 정적 분석을 해보고, 적용 유무 따른 실행시간 오류 결과를 분석한다. 분석 결과, 코딩룰을 이용하면 실질적으로 실행시간 오류 발생을 막을 수 있고, 적용 과정에서 기타 다른 실행시간 오류들 또한 해결됨을 확인하였다. 위 결과로 본 논문에서는 의료 분야의 특성을 고려한 특화 코딩룰의 필요성을 제시한다.

• The KIPS Transactions:PartA
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• v.11A no.5
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• pp.313-318
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• 2004

In this paper, we suggest a checkpoint and recovery facility for the fault-tolerable process which is expected to be executed for a long time. The basic concept of the suggested facility is to allow the process to be executed continuously, when the process was stopped due to a System fault, by storing the execution status of the process periodically and recovering the execution status prior to the fault was occurred. In the suggested facility, it does not need to modify the source code for the fault-tolerable process. It was designed for the user to specify directly the file name and the checkpoint frequency, and two system calls(save, recover) were added. finally, it was implemented on the Linux environment(kernel 2.4.18) for checking the feasibility.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.59-62
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• 2005

웹 상에서 XML 로 기술된 데이터가 증가하고, 이를 이용하여 의미 있는 데이터를 검색하는 것의 중요성이 커지고 있다. 웹 상에서 더 좋은 검색 성능을 보이기 위해 XML 질의 결과를 캐쉬하는 방법에 관한 연구들과 캐쉬의 저장 공간과 다양한 질의를 캐쉬에 저장하는 것에 한계가 있기 때문에 캐쉬 교체 기법에 관한 연구들이 있었다. 기존의 XML 캐쉬 교체 정책에는 질의 결과를 교체 단위로 하는 방법과 질의 결과 내의 각 경로들을 교체 단위로 하는 방법이 있는데, 첫번째 방법은 효율이 상대적으로 낮고 두번째 방법은 높은 효율에 비해 교체 연산을 수행하는 부담(overhead)이 크다는 단점이 있었다. 본 논문에서는 위 두 방법의 단점을 해결하기 위해 2 단계로 교체 희생자를 선택하는 방법을 제시한다. 질의 결과들 중에서 교체 희생자를 찾고, 그 희생자 내의 모든 경로들 중에서 다시 교체 희생자를 찾는다. 이는 각 질의 내의 경로가 교체 희생자가 되어 캐쉬 효율을 향상 시키고, 질의 결과에 대해 먼저 교체 대상을 찾으므로 교체 희생자를 찾기 위한 연산을 수행하는 부담을 줄인다. 또한 캐쉬 적중률, 최근 접근 시간, 인출 지연 시간, 객체 크기를 고려하여 교체 희생자를 선택하는 교체 함수를 제시한다. 가상의 시맨틱 데이터에 대한 캐쉬 교체 시스템을 구현하여 본 논문에서 제시한 교체 기법과 교체 함수를 평가한 결과를 기술한다.

• Journal of Advanced Navigation Technology
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• v.15 no.2
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• pp.326-333
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• 2011

In the present study, we measured the performance (accuracy and reaction time) of the user in the virtual environment with see-through Head-Mounted Display system that includes 3D sound generated through Head-Related Transfer Function (HRTF) to investigate the feasibility of auditory display for a certain object's spatial information. To sum up the results of two experiments, when presenting location information of the object with 3D sound, it is desirable that information arrangement from the user should be an orthogonal pattern which is located with right angle, not a diagonal pattern. Like these results propose that spatial information presentation with 3D sound make the optimal object arrangement of virtual environment possible.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.2
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• pp.7-14
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• 2023

As the consumption paradigm shifts from 'possession' to 'subscription', the subscription economy market is growing rapidly. The subscription economy is characterized by the fact that consumers can pay for and purchase products and services and use them limitedly for a limited time. Therefore, this study examined the effect of subjective perception of the time (duration) of consumers' subscription service use on subscription intention according to the time presentation method (duration/date) of subscription service use. In addition, the effect of differences in time presentation methods according to the type of subscription service (utility/hedonic) on subscription intention was examined. As a result of the study, the willingness to subscribe was higher when offering by date than when offering by date. In addition, for subscription services consumed for practical purposes, there was no difference in the effect on subscription intention according to the time presentation method. appeared to be Based on these results, the theoretical significance and practical implications of this study were presented.

• Journal of Advanced Navigation Technology
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• v.14 no.4
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• pp.571-577
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• 2010

Driving aircraft requires extremely complicated and detailed information processing. Pilots perform their tasks by selecting the information relevant to them. In this processing, spatial information presented simultaneously through crossmodal link is advantageous over the one provided in singular sensory mode. In this paper, probability to apply providing visual spatial information along with auditory information to enemy tracking system in aircraft navigation is empirically investigated. The result shows that auditory spatial information, which is virtually created through HRTF is advantageous to visual spatial information alone in attention processing. The findings suggest auditory spatial information along with visual one can be presented through crossmodal link by utilizing stereophonic sound such as HRTF. which is available in the existing simple stereo system.

• Journal of The Korean Association For Science Education
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• v.20 no.1
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• pp.77-87
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• 2000

The purpose of the study is to understand the change process of middle school students' physics conceptions by the presented types of conflict situations. 274 middle school students were selected from one school in Pusan, however 257 students were participated in all the procedure of the study. After we classified students' physics conceptions into scientific and unscientific conceptions, presented three types of conflict situations. In this study three different cognitive conflict strategies were adopted; the first one is logical arguments(LCS: logical conflict situation), the second is actual demonstration(DCS: demonstrational conflict situation), and the third is two strategies together(DLCS). In this study, first, we investigated the change process of students' physics conceptions by three types of conflict situations. Second, we compared the effect of three conflict situations presentation, which includes positive effect by conceptual change from misconception to scientific conception and negative effect by conceptual change from scientific conception to misconception. Third, we studied characteristics of conceptual change by characteristics of conflict situations. In result, DLCS group and DCS group were more positive effect than LCS group in mechanics, DLCS group and LCS group were more positive effect than DCS group in electricity. It seems that mechanics are closely related to physical experiences, while electricity are more abstract.

• Journal of vocational education research
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• v.35 no.4
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• pp.155-176
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• 2016

This study analyzed content of and recognition on occupations shown from Technology Home Economics textbooks of the high school elective subject having a higher connection with the career development capability for the occupational world as shown from a curriculum analysis. Hence, this study selected 3 kinds of high school Technology Home Economics textbooks with a higher share from 6 in the 2007 revised curriculum and analyzed a frequency by characteristic of occupational content and recognition on description of a occupation. Content analyzed by researchers was examined by 2 school teachers to ensure the validity and objectivity of research findings. Research findings show that there is a great deal of frequency difference in occupations suggested by publisher and unit in the Technology Home Economics subject. Also suggestion frequency of the occupational classification by level from Korean standard industrial classification did not correspond to an actual situation of employment. Occupation names suggested from textbooks occupied 3.3% of those by Korean Occupation Dictionary, showing a higher suggestion ratio at occupations preferred by adolescents. In the textbooks, occupations were suggested from reading materials, photos and illustrations more than from texts. Recognition on descriptions of occupations showed for the most part the neutral(82.8%) and the positive16.2%)', and there was no biased intention even from some negative cases(1.0%). Based on research findings, this research has significance in that it suggested things to be considered for teaching career development capability in the high school Technology Home Economics subject and need for cultivating teachers' specialty to understand occupations and instruct career development. It also suggested improvements to be required for a new curriculum textbook.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 1999.12a
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• pp.485-491
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• 1999

총납기지연 최소화 문제에서 많은 할당규칙들이 개발되어져 왔는데, 대부분의 개발 배경이 모든 Job이 동일한 시작시간을 갖는 Single Machine을 대상으로 하였기 때문에 이 할당규칙들을 Job의 시작시간이 다르게 주어지는 문제에 그대로 적용했을 때는 만족할만한 결과를 얻기가 쉽지 않다. 따라서 본 연구에서는 다른 시작시간을 갖는 Single Machine문제에서 총납기지연을 최소화하기 위하여 먼저, 새로운 작업쌍 순서(Job Pair Sequencing) 할당규칙을 제시한다. 제시되는 할당규칙은 Job들간의 Sequence를 쌍으로 비교하여 총납기지연 측면에서 선행이 바람직한 Job을 선택한다. 그리고 제시된 할당규칙에 대하여 다수개의 Job에 적용 시 선택된 Job들간에 Transitivity 가 성립됨을 증명함으로서 총납기지연을 최소화 시린 수 잇.음을 증명하였다.